1. Field of the Invention
The invention relates to a braking system for applying braking force to a small jet propulsion surfboard when pulled by a traction rope.
2. Description of the Related Art
Some small surfboards are power-driven and jet-propelled as disclosed in Japanese Utility Model Laid-Open No. Hei 1-109499, entitled "Self-circling system for Surfboard", which will be partially described with reference to FIGS. 10(a) and 10(b) of the accompanying drawings.
FIGS. 10(a) and 10(b) show an example of how power-driven surfboards operate. Referring to FIG. 10(a), an engine is housed in a projecting part 151 at the rear part of a surfboard 150. The engine is activated in order to cause jet propulsion. A rider 152 on the surfboard 150 holds a grip 155 at the upper end of a rope 154 with their left hand in order to balance and slide the surfboard 150 on the water. The rope 154 is provided with a resisting member 156 near the grip 155.
As shown in FIG. 10(b), when the rider 152 falls from the surfboard 150 into the water, the rope 154 also falls into the water, thereby allowing the resisting member 156 to open in the water, which applies braking force to the surfboard 150, making the surfboard 150 turn in a direction shown by an arrow a. This prevents the surfboard 150 and the rider 152 from becoming separated.
There is a surfboard which is operated by jet propulsion and handled just like a motorcycle (such a boat is referred to as a "jet propulsion surfboard"). With the jet propulsion surfboard, the rider sits on a seat, grips opposite ends of a steering handlebar with both hands, advances the surfboard by operating an accelerator lever at the right end of the steering handlebar, and decelerates the surfboard or moves it backward by operating a lever at the left end of the steering handlebar. This jet propulsion surfboard is usually larger than the foregoing power-driven surfboard.
The jet propulsion surfboard may be able to efficiently decelerate or turn itself if it is provided with a component corresponding to the resisting member 156 of the cited reference No. Hei 1-109499 (hereinafter the component referred to as a "braking system").
However, since a jet propulsion surfboard is usually larger than a power-driven surfboard, its braking system has to be large in order to allow efficient deceleration or turning, compared with the resisting member 156 of the power-driven surfboard 150. The larger the braking system becomes, the more complicated it becomes in order to maintain the strength of the braking system. Therefore, installation of the braking system on the jet propulsion surfboard increases the number of components, weight and cost.